Flower parts and then some

Most if not all of the readers of this blog know their basic floral parts. Generally there's a perianth in two whorls, sepals and petals, and then there's the androecium composed of a whorl of stamens, and lastly one or more pistils. But not all flowers are so constructed. So here's Calycanthus, Carolina spice bush. It has a lot of floral parts. Perhaps you've never taken one of these flowers apart, part by part to have a look see, but TPP just loves taking flowers apart to see what makes them tick. Not only does this flower have lots of parts to some extent they grade one into another and don't fall neatly into the usual categories. Below the flower is a pair of bracts, leaves of reduced size. One is shown. Then you start peeling off the perianth parts which are not differentiated into sepals and petals. They are longer and greener at first (l-r, top to bottom in order of removal), and then they get broader and purple-red. They are all spirally arranged. As the perianth moves inward the parts get smaller and more curved. The tip becomes yellow in color (row three, 4th one). After the 31st perianth part (the number you find may vary), the next part is abruptly smaller, a stamen, which is not your typical stamen in form, no filament, sort of a chunky version of a perianth part with two pair of microsporangia. These continue to spiral inward and downward into the receptacle. In this flower there were thirteen stamens. The next parts were too small to easily remove so what remains in this image is the top of the receptacle with a transitional stamen-pistil and then the rest of the pistils.

The pistils are sort of semi-embedded in the receptacle, each pistil topped with a creamy-white stigmatic area. It's hard to know how many there are 14-15, because the small vestiges are probably not viable and barely visible light areas. The spiral of parts continues with the pistils getting smaller, which you can see starting with the largest pistil at about 5 o'clock (reddish structure is the base of a stamen, white oval inwardly adjacent is the largest pistil), then the next biggest one is at about 10 o'clock, and so on. Altogether there are 60 floral parts, often a multiple of 3, but often off one or two as well. Maybe now you understand why textbooks illustrate flowers with simple things like a lily as if it were typical. This is a flower for advanced learners, so take your shoes off and get to counting the parts! Enjoy.

Phactor Phollowers

About Me

When not otherwise occupied, this author works as an academic botanist, a purveyor of plant diversity, taxonomy, economic botany, and rain forest ecology. The opinions expressed in this blog represent only my own and are in no way connected to the policies of my employer or state whoever they may be. No public resources were used to create this blog although many more foolish things have been done with public monies. Queries, questions, can be emailed to: phytophactor at googlemail (which is abbreviated to gmail) dot com.